CITY ROOM; As Trade Tower Rises, It's Not Quite What Was Planned

By DAVID W. DUNLAP

Published: June 13, 2012

When President Obama visits 1 World Trade Center on Thursday, he will find a tower that is undeniably impressive and - even a year and a half before its scheduled completion - unquestionably a landmark of 21st-century New York.

But it is not exactly the tower New Yorkers were led to believe they would see when the plans were unveiled in 2006. Since the Durst Organization joined the Port Authority of New York and New Jersey in 2010 as the effective codeveloper of the project, it has revised the design in a number of ways.

''I think they've been few and minor,'' Patrick J. Foye, the executive director of the Port Authority, said in a telephone interview Monday. The authority has approved all the revisions.

Taken together, it is true, the design revisions will probably not much alter the presence of 1 World Trade Center on the city's skyline. But they may change its place in the civic consciousness, if the tower is perceived as too isolated or fortified at its base, or as having too little of a symbolic spire at its summit.

What was supposed to be a cascade of steps from the building's west plaza down to Vesey and West Streets will instead be a terrace, set apart from West Street by a blocklong landscaped planter. Durst has also eliminated a skylight set into the plaza that was supposed to bring daylight to the observation deck lobby below ground.

Rather than being clad in panels of prismatic glass, the 185-foot-high base of the tower will be covered in hundreds of pairs of 13-foot vertical glass fins set against horizontal bands of eight-inch-wide stainless-steel slats. The corners of the base will lose what was supposed to have been a gentle but distinctive outward slope.

The rooftop mast will no longer be enclosed in a sculptural sheath of interlocking fiberglass panels but will instead be an exposed latticework structure. This may affect whether the arbiters of building height include the mast in their calculations, which would bring the 1,368-foot tower to a recognized height of 1,776 feet.

If the result of all these changes is to lower the construction budget - something the Durst Organization has a strong financial incentive to do - that was not their purpose, said Douglas Durst, the chairman.

''We didn't make the changes to save money,'' he said. ''The changes were made in order to construct the building.'' Mr. Durst said some features specified by the architects at Skidmore, Owings & Merrill and the landscape architects at Peter Walker & Partners would have been all but impossible to build and maintain.

Whatever the motivations, savings worth millions of dollars have been identified, though neither the Durst Organization nor the Port Authority would estimate the amount.

Durst originally sought what would have been, in essence, a construction management fee of $35 million for what it envisioned as five years of work. The authority was unwilling to pay that amount. Instead, a deal was negotiated under which Durst would receive a $15 million fee and be entitled to a percentage of any ''base building changes that result in net economic benefit to the project'' - cost savings, in other words - that Durst had initiated and recommended.

In August 2010, the Port Authority board authorized incentives to Durst of 75 percent of any savings it realized up to $12 million, and 50 percent of any savings it realized beyond $12 million. Subsequent negotiations changed the benefit to Durst, with a formula running from 75 percent of savings up to $24 million, stepping down to 50 percent, 25 percent and 15 percent as the savings increased.

After a year in which the design revisions have come out publicly in dribs and drabs, Mr. Durst and his senior project manager, Tony Tarazi, sat down with a reporter last week to discuss the changes comprehensively.

The biggest revision that has received the least public attention is to the large triangular plaza on the west side of 1 World Trade Center. Because of a grade change on the site, the plaza is up to 5 feet 8 inches higher than the surrounding sidewalks. The original plan called for broad stainless-steel steps to address that height difference.

''We wanted to create as much plaza as possible,'' Mr. Durst said. ''We didn't see that the steps added anything, because most people don't come in from the west.'' Durst executives also questioned the wisdom of using stainless steel as a walking surface.

Peter Walker & Partners stepped away from the project and was replaced by Mathews Nielsen, of which the landscape architect Signe Nielsen is a principal. The Walker firm remains involved in the the 9/11 Memorial.

Under the new design, the plaza would occupy a terrace above sidewalk level, reached by a stairacse on Vesey Street. The terrace would be paved in granite, have about a dozen sweetgum trees and a blocklong planter that would double as seating.

''The stainless-steel pavers turned out to be very slippery,'' Mr. Foye said, ''and there would have been times of inclement weather where there was a danger.''